Rivet set



Jain. '12,:1943. MLM. KENNEDY arm. 7 2,307,795

I 'RIVET SET Filed July 22, 1941.

vI V

' 1 'SHANK 2! HEAD INVENTORS BY Ken/7E0 Patented Jan. 12, 1943 UNITED STATE RIVET SET Matthew M. Kennedy, Philadelphia, and James E. McCambridge, Drexel Hill, Pa.

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) 6 Claims.

This invention relates to a rivet set, and has for an object to provide an improved rivet set of great durability.

A further object of this invention is to provide a rivet set whose life is many times the life of the prior rivet set, although it differs from the prior rivet set in what appears to be but a slight change in shape.

The life of the prior rivet set in actual practice was found to be extremely limited, serious breakage of such prior rivet sets having been experienced during a large job, the failure of such prior rivet sets being so rapid as to make the cost almost prohibitive. As one example, it was found that a rivet set failed after driving a total of only forty-seven 1 diameter countersunk H. T. S. rivets, While the rivet set of the present invention has averaged approximately 11,000 similar rivets without failure.

With the foregoing and other objects in view, the invention consists in the construction, combination and arrangement of parts hereinafter described and illustrated in the drawing, in which:

Fig. 1 is an elevational view of the improved rivet set of this invention; and

Fig. 2 is a similar view of the rivet set of the prior art.

There is shown at l the improved rivet set of this invention, while there is shown at H the prior type of rivet set over which the present invention is an improvement. The head l2 of this rivet set is identical with head I 3 of the prior type set ll and is connected through a flange kl to the shank l5, just as in the prior type the head I3 is connected through a flange Hi to the shank l7.

In the prior type the shank l1 joins the enlarged flange l6 by means of an abrupt fillet l8. With this prior type of fillet it was found that the life of this rivet set is very short, breakage of this rivet set usually occurring along the line 20 after only a very limited number of rivets had been operated on, the number of operations often being less than one hundred. While investigating such failure it was found that the breakage was apparently due to stress concentration at this fillet [8 between the shank l! and the head l3 of the rivet set I I. It was concluded that if this stress concentration could be reduced, breakage would stop and the life of the rivet set would be prolonged. With this thought in mind, the idea was conceived of reducing the stress concentration at the fillet l8 between the shank l I and the ENT OFFICE head l3 by recessing the shank at this point and forming a larger and more gradual fillet.

Accordingly, the fillet connecting the shank 15 of the improved rivet set It to the flange M and head I 2 commences from a pointil at a substantial distance from the flange It. From this point 21 the fillet 22 is first recessed to the point 23 and then merges gradually out toward the fiange 14. Comparing the fillet 22 of this improved rivet set invention H) with the fillet ll} of the prior type rivet set II, it will be observed that the length of the improved fillet 22 is about three times the length of the prior'fillet l8, and in addition it reduces the diameter of the shank IS a slight amount before it gradually enlarges again to meet the flange I4.

With this apparently simple change in shape, the life of this rivet set has been found to be hundreds of times longer than the life of the rivet set ll of the prior art.

In operation, the new rivet set Ill is used in the identical manner that the old rivet set I l was used; that is, the shank I5 is inserted into the pneumatic hammer and the head I2 is operated against the rivet being peaned over, the only difference in operation being that with the prior type of rivet set a new rivet set had to be inserted in the pneumatic hammer after every fifty to one hundred rivets, while the rivet set l0 operates on thousands of rivets without change.

Other modifications and changes in the numher and arrangement of the parts may be made by those skilled in the art without departing from the nature of this invention, within the scope of what is hereinafter claimed.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

Having thus set forth and disclosed the nature of this invention, What is claimed is:

1. In a rivet set consisting of a head, a fillet, a flange, and a shank connected to the flange by the fillet, the improvement of an enlarged gradual and slightly recessed fillet.

2. In a rivet set consisting of a head, a fillet, a flange, and a shank connected to the flange by the fillet, the improvement of an enlarged gradual and slightly recessed fillet, said fillet having a width several times the depth thereof.

3. In a rivet set consisting of a head, a fillet, a flange. and a shank connected to the flange by the fillet, the improvement of said fillet comprising a shallow annular groove.

4. A rivet set comprising a riveting head, a flange, a shank and a fillet connecting the shank to the flange, said fillet comprising a shallow annular groove.

5. A rivet set comprising a riveting head, a flange, a shank, and a fillet connecting the shank to the flange, said fillet comprising a shallow annular groove, said groove extending somewhat below the peripheral surface of said shank.

6. A rivet set comprising a riveting head, a 

